The Sena Prism is a solidly built, Bluetooth 4.0 action camera, first introduced on webBikeWorld in the Sena Prism preview from October 2013.
The Prism records video in 1080p at 30fps; 720p at 30 or 60fps and 480p at up to 120fps.
Voiceovers can be recorded using Sena or other brands of Bluetooth intercoms for narration and it’s also possible to record group intercom conversations.
While as of yet the Prism can’t be controlled by voice commands, it can be paired with a system like the Sena 20S (review) and video recording on the Prism can be turned on and off with a push of the jog dial on the intercom.
This makes it very easy to get good action video in short clips. The menu system in the Prism is also accessible by using the jog dial on the intercom.
The Prism kit comes with a huge variety of camera mounts, from goggle mounts to suction cup mounts to helmet mounts.
As we have stated many times, when it comes to motorcycle action cameras, it’s all about the mount and everyone should be happy with the selection included in the Prism kit.
Sena has also developed what we can easily call the best action camera helmet mounting system we’ve seen.
It’s a metal helmet mount that is similar to a standard intercom helmet mount and the Prism attaches to it with an adjustable ball and socket type system.
The system is as solid and easy to use as you’ll find and it makes a real difference as a stable video recording platform.
Sena has also published an app that allows Prism owners to adjust camera settings but it does not have a live view capability and the Prism camera doesn’t either, unfortunately. But Sena said they’re working on a possible update to correct that oversight.
The Prism takes excellent quality video that is smooth and evenly exposed with good color rendition.
There’s a lot more to discuss regarding this new action camera and we’ll try to cover as much as possible in this review.
We also created an extended-length video describing many Prism features and that is included below.
The Prism action camera has a rectangular box shape that is a variant on the “tube” (long forward-facing) action camera form factor. It’s not a big device, measuring just 63 mm x 44 mm x 23 mm and weighing about 125 grams with battery.
The lens has a push-on rubber/vinyl cover that holds pretty well but can be easy to lose, so be careful. The flat lens is recessed behind a plastic surround that offers a modicum of protection.
This should help to prevent damage, unlike the convex lenses of other action cameras like the GoPro Hero 3 (review) that need a waterproof housing for lens protection.
The Prism has a very solid feel and excellent build quality.
The only nit to pick is the rear cover that hides the mini-USB and HDMI connectors, the battery and the microSD card port.
This cover is a bit fussy to fit and the lock slider is difficult to close. It’s more or less a two-handed proposition, but be careful you’re not grabbing the lens when you’re pushing the door closed hard enough to get the latch to set.
Sena Prism Specifications
The Prism specifications and other details were described in our 2013 Sena Prism preview, but here are the specifications of the production version:
Lens: 3.5M pixel CMOS with f/2.0 aperture.
Field of view is 140 degrees.
Bluetooth 4.0, Headset Profile and Hands-Free Profile (HFP)
Bluetooth Audio Recording allows recording of your voice (not music) from your Sena Bluetooth intercom.
Bluetooth remote control using Bluetooth headsets.
The Sena Quick Release Motorcycle Mount mounting system.
Built-in microphone, Bluetooth headset voiceover mic or external Bluetooth microphones can be attached.
Voice prompts with your Sena intercom.
Video Modes: 1080p at 30fps; 720p at 30 or 60fps; 480p up to 120fps.
Photo modes include single shot, time lapse and burst.
Water-resistant for use in inclement weather. Includes waterproof housing in kit.
One feature missing on the current version of the Prism is a live view capability in the camera or in the app.
Sena Prism Features
The sensor is a 3.5 megapixel CMOS type.
LCD Live View
The Prism connects with the app via Bluetooth, not WiFi, so there is no live view capability in either the camera or the app. Sena said they’re trying to develop a solution for this.
The Prism captures video in .MP4 H.264 format at 1080p 30fps; 720p at 30 or 60fps or 480p at 120fps for slow-motion. At 30fps, the video bitrate averages around 11,300 kbps.
Audio is recorded at 128kbps at 30fps in two channel stereo at 48kHz. The Prism records in two channel stereo, according to the owner’s manual, although it appears to have only a single microphone in front.
The Prism can record sound from a Bluetooth intercom system, Sena or other brands.
This is useful as a voiceover or for rider training. We have an example of this in the video below. Group connected conversations can also be recorded but at this time, streamed music can not be recorded.
The Prism can take photographs in the following resolutions and formats: 3.5MP (3:2); 3.2MP (4:3); 3.0MP (16:9); 5.0MP (16:9).
The camera has a burst shot mode that takes 10, 5 or 3 photos. There’s also a time lapse mode for photographs and video of 1, 3, 5, 10, 30 and 60 seconds (not available in 480p/120fps or 720p/60fps.
The Prism lens has a field of view of 137 degrees or 90 degrees, set by the user in the menu system. The lens has an f2.0 aperture.
ISO is automatic as is white balance.
The Prism battery is 1100 mAh. It lasts up to about 2 hours on a full charge and takes about 3-4 hours to charge. Sena doesn’t publish a CIPA battery life estimation.
The Prism uses a microSD memory card. We couldn’t find a specific recommendation for card types or sizes but the Prism owner’s manual (not included with the kit but available as a .pdf download) lists 32GB as the maximum size.
We suggest using a Class 10 card for video recording; we prefer the SanDisk Ultra, available here. The memory card is not included in the camera.
The Prism kit comes with the camera, the Li-Ion rechargeable battery and a removable rubberized lens protector.
The kit contains an enormous array of camera mounts, including a waterproof housing and an additional “skeleton” door for non-waterproof sound recording.
Also a USB cable for charging and data, the metal helmet clamp mount, helmet stick-on mount, top mount, handlebar mount, two suction cups and a dual suction cup mount kit and other accessories, mounting parts and a quick start guide.
Power adapters, wall chargers and all of the parts are also available as optional accessories.
The Prism is very easy to use with or without connecting to an intercom.
Once the camera is charged, fire it up by pressing and holding both the “M” (Menu) and “S” (Select) rubberized buttons on top. The camera starts and you’re ready to go.
The various menu choices are selected by pressing the M button, then you can dive down into the menu system by using the S button.
If video is selected, press the red dot S button and the camera will start recording in your chosen resolution. Press again to stop.
Sena recommends pairing a smartphone to the Prism in headset pairing mode and to the 20S (or other Sena intercoms) with intercom pairing mode.
The Sena Prism app allows you to change settings in the camera without using the menu system. You’ll have to pair your smartphone to the Prism first.
There really aren’t many settings most owners will need to change anyway, and it’s easy enough to do it in the menu system. But the app does come in handy once the Prism is mounted on your helmet and you want to quickly change settings.
Unique Prism Capabilities
The Prism is the first action camera with Bluetooth 4.0 ability to control the camera through an intercom link. But that’s not all: the Prism can also record your voice or paired group intercom conversations.
If the Prism is paired with a Sena intercom like the 20S, you can move through the menu system by pressing the jog dial and turning it.
This can be a bit tricky, especially when you’re on the bike wearing the helmet and wearing heavy gloves, so it’s not really the primary way we like to change menu settings.
Using the jog dial to start and stop video recording is easy however. Press and hold the jog dial for about 1 second and the recording will start and the Sena intercom spoken status announcement voice will let you know. Press and hold again to stop recording.
This saves battery life and also allows you to record just the video clips you want…just remember if you have the video recording on or off.
It would be nice if there was an occasional beep or something in the speakers that lets you know that the Prism is still recording.
Sena Prism Video Quality
The Prism is definitely in the top tier for video quality compared to other action cameras we’ve reviewed. The 1080p video is smooth and very nicely exposed, with accurate color rendition.
The Ricoh WG-M1 has very good video quality and the Sena Prism is also a contender.
The Replay XD Prime X is probably the champ in this batch but technical difficulties with the camera have proven difficult, making it hard for us to recommend.
Although the overall exposure and color accuracy from the Prism video is excellent, our Prism is just a touch less sharp and smooth than the BlackVue Sport 500 (review) and the GoPro Hero 3 (review) and the colors aren’t quite as accurate as those two.
If you never watched identical video taken simultaneously with all three cameras, you’d probably never notice, so there’s not much to worry about.
The caveat is that while the video taken with most of the action cameras recently is good quality, it can’t compare to a dedicated video camera or with some of the DSLRs or mirrorless cameras.
As is the case with most action cameras, viewing the video on a large screen close up will expose some artifacts and blurred details.
But the Prism does have noticeably better video quality than many other action cameras and the video looks very good when viewed in a smaller screen size.
Note also that correctly capturing action video from a moving vehicle like a motorcycle is notoriously difficult and the online video services like Vimeo or YouTube don’t really take to fast-moving video very well.
The Prism also does not have image stabilization like the Ricoh WG-M1 but the Sena helmet mount makes up for that with its solid mounting ability.
Here’s a raw sample from the Prism (.zip file), about 20 seconds of .MP4 video taken at 1080p/30fps. It’s a 75MB file, so please go easy on the downloads.
The small size and light weight of the Prism, combined with the vast array of mounts that come in the kit, make this action camera one of the easiest and most secure to use on a motorcycle.
That alone is a huge difference between the Prism and all of the other action cameras reviewed on webBikeWorld, none of which have the “perfect” mounting system.
Indeed, the mounts that come with every other camera we’ve reviewed could be characterized by one word: pathetic.
Sena obviously had motorcyclists primarily in mind when they designed and developed the Prism; more than can be said for every other action camera in memory.
We almost never use the word “best” on webBikeWorld, but in our opinion, the Prism kit comes with the best currently available helmet mounting system for a motorcycle helmet.
It’s a metal helmet mount that looks very much like the standard motorcycle intercom mount — you know, the one you push up between the helmet shell and EPS and which secures with a couple of hex screws.
The narrow rectangular shape of the Prism is perfect for this design; clip the camera on to its ball-end holder, secure the holder in a friction screw adapter and snap the adapter on the mount. It’s secure, it’s easy to adjust and it’s out of the way.
It’s also easy to mount the Prism using one or both of the suction cup mounts included in the kit. Or, you can use one of the stick-on helmet mount systems if the metal intercom-style mount clip doesn’t fit your helmet.
The only difficult orientation for the Prism would be a chest mount — something that’s easy to do with the GoPro style “Big Box”, forward-pointing-lens cameras.
However, there’s a downside to including all of these mounts in the Prism kit: the list price. The Sena Prism currently lists for $399.00.
One wonders how much the list price might have been reduced if the camera came with just the helmet mount and the rest were extra-cost accessories.
Since the helmet mount works so well, motorcyclists will probably use it exclusively, making many of the other included mounts redundant.
Unique Prism Capabilities
UPDATE: More Prism Features
The Prism has so many features, it’s difficult to remember them all (and some can be found only by digging deeply into the owner’s manual). Here are some other features, several of which are unique to the Prism:
Voice Commands: According to Sena, the 20S has a “secret” voice command to start and stop the video and photo recording in the Prism.If you speak the command “Prism” while the 20S is connected to the Prism, it will start capturing video. This function will be included in firmware updates for other Sena intercoms. Note that we couldn’t get this to work in our 20S/Prism pair.
Handlebar and Wristband Remote Control for the Prism will be released in the Spring. These were described in the webBikeWorld Sena report from the 2014 AIMExpo show.
Feedback While Recording Video: While you record the video, you may realize the voice is heard differently. There is a side-tone. By using this feature, you may know whether it is being recorded or not.
Voice Capture: The Prism is unique in that there are currently no other action cameras that can record voice while riding.
Audio Settings: Sena recommends setting the audio (chapter 9.3) as internal mic gain=high, Bluetooth mic=on, UHD mode=on, auto mute=on. The auto mute function will disable the internal mic once it is connected to Bluetooth headset.Tests show that the ideal audio recording is to turn off the internal mic when you use the Bluetooth voice recording. If Bluetooth is not connected, set the Prism using the mic with high internal mic gain.
Voice Recording is useful for motorcycle vlogging, motorcycle riding schools, motorcycle touring events and more.
Firmware Updates: Firmware updates are scheduled for the Prism to improve the system continuously. Also, other Sena communication systems will be updated as well along with the Prism update.
Use While Charging: You can use the Prism while charging as other Sena products via the miniUSB port in the rear. Theoretically, you don’t need to replace the battery while riding.
Splash-Proof: The Prism is water-resistant without the waterproof case. This reduces the actual form factor and makes the camera more useful.
Upcoming Accessories: New accessories will include a battery charger and battery pack.
Sena pushes firmware updates quite often for their products. The Prism has an update so be sure to check the information that came with the camera and follow the instructions to install the latest firmware update.
wBW Video: Sena Prism Overview and On-Road Examples
NOTE: YouTube and Vimeo compression significantly degrades the quality of the video from the original and it does not like fast moving video like motorcycle riding. Select the highest quality available under the “gear” icon in the YouTube video above to optimize your viewing.
The Sena Prism could be called a revolution in action cameras for motorcycle use. The camera and its mounting system were designed from the outset for motorcyclists and it shows.
The Prism’s helmet mounting system makes a big difference compared to any of the other action cameras we’ve reviewed and the Prism comes with just about every type of mount you’d need.
But that isn’t enough, of course, and the Prism also takes excellent quality video that’s right up there with the best. It’s also very easy to use and the camera and its accessories have a very solid build quality.
The icing on the cake is the connectivity options included. The Prism can be controlled by a Sena intercom and voiceovers can be recorded on the video with Sena and other brands of Bluetooth intercoms.
The only downside to all of this is the price. The Prism “system” is at the high end of the motorcycle action camera price spectrum at $399.00.
You do get every mount you’ll probably ever need, but you probably won’t need many after using the helmet mount.
Bottom line? The Sena Prism would make an excellent choice for motorcycle action camera video for anyone from first-time videographers to experienced users. It has no equal for helmet mounting, so for motorcyclists, it may be the best choice.